Hi Two examples:
Linear LT1764 ($4 to $8 depending on qty): Low drop out, low self generated noise, lots of power, lots of current. Needs help past ~ 8 KHz for crud rejection. Linear LT1963 ($3 to $5 depending on qty): Better crud rejection, higher dropout, lower power, lower current. Needs help past ~ 100 KHz. Both are adjustable parts. You can tailor them to match the supply you have. My preference is the first part with a nice coil (or better two) in front of it. There are a lot of parts designed for switchers that will do a fine job. Since the regulator needs at least 10 uF in front of it, the coil(s) can be in <= 2 mHy and do fine. I get my coils on the e place so I can't recommend a specific part. You can also do just fine ripping them out of dead switching supplies. One thing you could do if cost is no object - cascade several of the parts with a bit under a volt across each one. +15 volts to +12 volts with three stages of isolation. Provided ground loops don't get you, there won't be much line related stuff at the output of that cascade. Bob -----Original Message----- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Michael Baker Sent: Monday, April 26, 2010 11:02 AM To: time-nuts@febo.com Subject: [time-nuts] Which voltage regulator chips offer good performance...? Hello, Time-Nutters-- Bob Camp said: > snip > ...stability is not the only issue. > Crud on the power supply is an issue as well. > Some of the ultra low drop out regulators > are not real good crud blockers. ----------------------------------------------- So... This would seem to bring up the question of which 3-terminal regulators ARE good (if not "good" then which are the "best"?) providing both stability -AND- clean, crud free output? How about old standby regulators such as the 723? Problem there is that the stand-alone chip is only good for really low current. For years I have been using general purpose 3-terminal regulators sometimes with carefully selected low impedance capacitance on the output. In some cases I have found that a high-gain transistor in the output configured as a "capacitance multiplier" serves to handle current load spikes but is only a nominal help in cleaning up crud on the output. Comments? Suggestions? Mike Baker ------------------------------------- _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.